Cause of helicopter crash determined

  • 2006-02-22
TALLINN 's Investigators have determined that a faulty servo led to the crash of the Sikorsky 76C helicopter last August that took the lives of 14 people.

A six-month investigation, much conducted in a U.S. laboratory, found that the Finnish-owned helicopter's front servo, showed that parts of the plasma-sprayed coating that are made from a mix of copper and aluminium had broken off from the piston crown. The servo, which controls the helicopter's throttle, fell apart.

Experts explained that, after breaking off, the two large pieces of the servo layer blocked one of the ports by which the device is operated. This, in turn, caused the servo to break down completely, which triggered an unexpected attack of the rotor blades and the subsequent crash.

The ministry pointed out, however, that the conditions which led to the servo's dismantling had to be proved in further tests and surveys. Since a servo is a piece of high-tech equipment, all laboratory examination requires long-term planning and careful execution, a ministry spokesperson added.